Waterpump Replacement

[Chris142]

I wouldn't pump it up to 30 psi. Maybe 20 at the most.

I have only seen one of those pumps leak from the weep hole. They often leak from the gaskets between the block and the water pump.

The Napa pump if you need a pump comes with all the necessary parts. The others only have the water pump and the 2 block to pump gaskets. So then you must go searching for the other gaskets for the thermostat housing or use silicone on the old one.

Once you get the intake boot and fan shroud off you must remove the big nut that holds the fan clutch on.

Then remove the upper and lower hoses then the 2 small heater hoses. Now remove the six bolts with 10mm heads and the pump will fall off. Be care full that you don't ding the radiator with it as it's pretty big and awkward.

That's it. It's that easy. Clean up the gasket surfaces and reinstall the new parts.

As I already said I have only seen one of those pumps leak and it had over 200k on it. Since cash is tight you may be able to get away with just replacing the 2 inexpensive gaskets instead of the whole pump.

 

[RoGuE]

I tried the pressure tester and I can't get it to work. The coolant tank has a hole near the top of it that the cap would normally cover (excess coolant vents through it down a hose through the wheel well. Without the cap on though, nothing covers it and when you pump the tester, pressure won't build up.

I tried just removing the hose and keeping my finger over it but after pumping it up only a few psi and then removing my finger the coolant rose and and came out a little. Is this a unique coolant tank or am I missing something?

I still haven't confirmed it's the water pump (weep hole doesn't look wet, and I can't see where it meets the block), but that it is coming from the area. What should I do now? Can I just assume it is the water pump and change it?

 

[Jimmy9190]

Given the symptoms you have - coolant puddling under the truck and coolant stains and possible leaks on the front of the engine, and considering what a lot of other GM owners and guys who know a lot about it have said here, I would just go ahead on and replace the water pump. Sounds like Chris in the above post has seen his share of this exact same problem. If money is tight, he has a good idea with only replacing the gaskets, but I myself would rather just do the job only one time and be done with it. If it were my truck, I would replace both gaskets and the pump too.

 

[caravanmike]

we have had 2 tahoes (fleet at work)with the 5.3L leak antifreeze around 130,000 miles (out the weep hole).

 

[Chris142]

Originally Posted By: RoGuE
I tried the pressure tester and I can't get it to work. The coolant tank has a hole near the top of it that the cap would normally cover (excess coolant vents through it down a hose through the wheel well. Without the cap on though, nothing covers it and when you pump the tester, pressure won't build up.

I tried just removing the hose and keeping my finger over it but after pumping it up only a few psi and then removing my finger the coolant rose and and came out a little. Is this a unique coolant tank or am I missing something?
Your missing the proper adapter for that bottle. Put a bolt in the overflow hose then pump it up and let it sit.

 

[scott37300]

Plug the overflow hose and pump away, do not go to 30 PSI unless that is what your system is designed for, it should say what PSI on your radiator cap. If not call parts store or get a manual to tell you what PSI to pump your system up to, or google it. You might need an adaptor for the pressure tester, depends on vehicle.

I would have no problem ordering from rockauto, I order a lot of stuff from them and they have unbeatable prices and quick shipping.

 

[beaker60]

Hey Rogue,,if you haven't done your waterpump yet and you need help,,I live in Calhoun,,,I don't know where you reside at,,,but I was a GM tech for about 25 years and I have done a lot of those pumps,,,I'm retired now and not doing anything is driving me nuts,,,so like I said,,if you need or want help,,,give me a shout,,,no charge,,,just be glad to help someone out.

 

[steve20]

wife's 05 Tahoe 5.3 has been slowly leaking from one of the gaskets for about a year now-not enough to even spot the driveway, so it is way down on the list. Nice video


Steve

 

[SteveSRT8]

Rogue, it's one of the easier W/P jobs there is on a V8.

We've done it a dozen times here on our fleet trucks. Make sure you get a NEW pump, I buy mine at Autozone and they will cheerfully hand you a new one 5 years later!

 

[RoGuE]

Originally Posted By: Jimmy9190
Given the symptoms you have - coolant puddling under the truck and coolant stains and possible leaks on the front of the engine, and considering what a lot of other GM owners and guys who know a lot about it have said here, I would just go ahead on and replace the water pump. Sounds like Chris in the above post has seen his share of this exact same problem. If money is tight, he has a good idea with only replacing the gaskets, but I myself would rather just do the job only one time and be done with it. If it were my truck, I would replace both gaskets and the pump too.


Yeah, I guess there is little sense in taking the old pump off just to put it back on.

Originally Posted By: Chris142
Your missing the proper adapter for that bottle. Put a bolt in the overflow hose then pump it up and let it sit.


That worked like a charm. I couldn't find a bolt big enough so I just shoved my 3/8 ratchet extension in the end that that worked like a charm. It still leaked air slightly from from where the hose met the bottle, but it was slow enough to hold pressure for a few minutes. After pumping it up to 15psi, it started leaking out a lot fast from the water pump area, so I guess that is enough of a confirmation.

Originally Posted By: beaker60
Hey Rogue,,if you haven't done your waterpump yet and you need help,,I live in Calhoun,,,I don't know where you reside at,,,but I was a GM tech for about 25 years and I have done a lot of those pumps,,,I'm retired now and not doing anything is driving me nuts,,,so like I said,,if you need or want help,,,give me a shout,,,no charge,,,just be glad to help someone out.


I appreciate but you're about 2 hours away. I'm down in the Buford/Suwanee area by Lake Lanier. Otherwise, it would be great to have a hand from someone who knows how to do it already. lol

I can't get a good look of where it meets the engine block, but there is nowhere else (hoses, clamps, etc.) that it is coming from. This of the bottom of the water pump after the pressure tester made it leak faster.





Also, this is the A/C belt (there lowest belt in the image with orange on it). I guess those giant cracks in it warrant a replacement? lol:




I'll try to tackle this job next Tuesday. I feel well prepared thanks to all the great answers here.

 

[The_Eric]

I'd say so... When you replace the belt, make sure you replace the tensioner. Give the main tensioner and idler a spin and listen to the bearings.

Lastly, I know others have probably made the suggestion to replace the thermostat, but I'll chime in and say it again - replace it now and use an OEM stat.

 

[Jimmy9190]

The AC belt looks like it is in bad shape and needs to be replaced. The main serpentine belt looks good though, at least in the picture. If you get your new pump at Napa, their belts are good quality too. Napa may have 2 different belts available, one less expensive than the other. Either one will do fine, they are both made by Gates.

You shouldn't have much trouble with the job. Even if you do, there's a lot of guys on here who are very familiar with it and can help if you need it. Good luck and let us know how it all turns out.

 

[RoGuE]

I finally found a big adjustable wrench I have (I've been searching for it for days, it's an OLD Craftsman that is easily 40 years old). Unfortunately it is only a 10" and not big enough to fit over the nut. I would go to Harbor Freight but it's about 20+ miles away and doesn't seem worth the drive. Most other stores a 12" adjustable is about $20 (if 12" is even big enough) and the less tools I have to purchase and store in my tiny garage the better.

Earlier in this thread Jimmy mentioned that Autozone should rent a fan clutch tool set. Is that what I should ask for if I go this route? I also have a pipe wrench that would fit, but I'm sure it would tear that nut up with the amount of force I need to use.

And one final question for this post, do I need to torque the bolts on the water pump? Or is it possible to just snug them up? All I have is a 1/2" HF torque wrench that is 20-100 lb-ft.

 

[Jimmy9190]

This one should work fine:

http://www.harborfreight.com/15-inch-jumbo-adjustable-wrench-39619.html

In this case, HF would be worth the trip. Personally I have found the HF Pittsburgh brand wrenches to be pretty good quality. I have a wrench like that one in the link that I bought a long time ago at Discount Auto Parts, long before they merged with Advance. I remember I paid about 20 bucks for it, and that was back about 13 years ago.

Autozone and Advance do rent a kit (for free, you pay a deposit up front and get the deposit back when you return the kit. Essentially you are just buying and then returning the tool kit) for removing the clutch fan. And that is what you should ask for when you rent it. Your pipe wrench may be too big to fit down in there on the nut, but is worth a try. You are probably right about it tearing up the nut.

Check the Haynes book for your torque values on the water pump. It's probably online too, if you Google it I'm sure it's on a Chevy forum somewhere.

 

[Chris142]

Use your pipe wrench. A few nicks on the nut wont hurt anything. The water pump bolts just need to be snugged up.

If you are just going to replace the gaskets behind the pump you should be able to get the pump off and back on w/o taking the fan off.

 

[Herz]

Originally Posted By: Chris142
Use your pipe wrench. A few nicks on the nut wont hurt anything. The water pump bolts just need to be snugged up.

If you are just going to replace the gaskets behind the pump you should be able to get the pump off and back on w/o taking the fan off.


+1
dont take the fan off if your just replacing the gaskets. Just be careful with the radiator.

 

[RoGuE]

At nearly 120k miles now, and being used about 6-7 days a week, including the five days my dad drives 20 miles each way to work, I'm not even thinking twice about just changing the whole thing out.

I may have to postpone it for a few more days. Being daily driven, it is hard to schedule a time to do it. It doesn't seem to be leaking at all these past few days though. Seems to be no rhyme or reason to when it leaks.